You are what you eat
Simon Thornley MBChB, FAFPHM
Overview • What makes a food or drink healthy?
• What I was taught about food at med school • Why I started questioning these beliefs • Using food as a medicine!
When you go shopping…
• What makes a food healthy?
• Saturated fat causes cardiovascular disease • Eating too much fat makes us fat • Eating is about rational food choices
• Too much salt is bad for us • Sugar is a harmless treat • Low carb diets are fads and don’t work
What I thought I knew…
Saturated fat causes cardiovascular disease Is this true?
The Oxford Textbook of Medicine “Foods that increase the risk of coronary heart disease when consumed in large amounts … are rich in saturated or trans-unsaturated fatty acids, and dietary cholesterol.” J. I. Mann and A. S. Truswell
Diseases of overnourished societies and the need for dietary change: in The Oxford Textbook of Medicine, 5th Edition (2010).
Translation • “Eating animal fat (butter, cream, lard, dripping, chicken skin) leads to heart attacks”
What is the evidence?
Eating too much fat makes us fat If Energy in > energy out, then obesity
American Heart association: 1970s
What happened to our waist lines?
Obesity prevalence (%>= body mass index 30 kg / m )
30 20 10
30 20 10
30 20 10
Low carb diets are fads and don’t work How can eating energy dense food make us thin?
Low Fat vs. low carb vs. Mediterranean (n=322)
Shai I, Schwarzfuchs D, Henkin Y, et al. Weight loss with a low-carbohydrate, Mediterranean, or low-fat diet. N Engl J Med. 2008; 359:229 - 41.
Eating is about rational choices
Automatic eating • 40 secretaries (cross-over)
• Ate 4.6 more chocolates/day if at desk (& visible), rather than shelf 2m away Wansink B, Painter JE, Lee YK. The office candy dish: proximity’s influence on estimated and actual consumption. Int J Obesity 2006;30(5):871–5.
Tobacco Withdrawal Symptoms
Irritable Depressed Restless
low GI, whole grain carbs > protein > fat
Practical points • Not a diet!
• Limit certain foods • Others unlimited.
• Sugar, starch withdrawal • (stevia, sugar alternatives)
Practical advice •
Eliminate • Sugary drinks (soft drinks, cordials, fruit juice) • Sugary desserts, breakfast cereals, lollies, milk chocolate, biscuits
Limit • Starches: bread, pasta, potatoes, kumara, noodles, rice, couscous • Aim for